﻿using System;
using System.Collections;

namespace Velocity4Net.Runtime.Res
{

    /*
     * Licensed to the Apache Software Foundation (ASF) under one
     * or more contributor license agreements.  See the NOTICE file
     * distributed with this work for additional information
     * regarding copyright ownership.  The ASF licenses this file
     * to you under the Apache License, Version 2.0 (the
     * "License"); you may not use this file except in compliance
     * with the License.  You may obtain a copy of the License at
     *
     *   http://www.apache.org/licenses/LICENSE-2.0
     *
     * Unless required by applicable law or agreed to in writing,
     * software distributed under the License is distributed on an
     * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
     * KIND, either express or implied.  See the License for the
     * specific language governing permissions and limitations
     * under the License.
     */





    /**
     * Interface that defines the shape of a pluggable resource cache
     *  for the included ResourceManager
     *
     * @author <a href="mailto:geirm@optonline.net">Geir Magnusson Jr.</a>
     * @version $Id: ResourceCache.java 1780734 2017-01-28 19:21:08Z cbrisson $
     */
    public interface ResourceCache
    {
        /**
         *  initializes the ResourceCache.  Will be
         *  called before any utilization
         *
         *  @param rs RuntimeServices to use for logging, etc
         */
        void initialize(RuntimeServices rs);

        /**
         *  retrieves a Resource from the
         *  cache
         *
         *  @param resourceKey key for Resource to be retrieved
         *  @return Resource specified or null if not found
         */
        Resource get(Object resourceKey);

        /**
         *  stores a Resource in the cache
         *
         *  @param resourceKey key to associate with the Resource
         *  @param resource Resource to be stored
         *  @return existing Resource stored under this key, or null if none
         */
        Resource put(Object resourceKey, Resource resource);

        /**
         *  removes a Resource from the cache
         *
         *  @param resourceKey resource to be removed
         *  @return stored under key
         */
        Resource remove(Object resourceKey);

        /**
         * Removes all of the resources from this cache.
         * The cache will be empty after this call returns.
         * @since 2.0
         */
        void clear();

        /**
         *  returns an Iterator of Keys in the cache.
         * @return An Iterator of Keys in the cache.
         */
        IEnumerable enumerateKeys();
    }
}